Exploring the Long-Term Impact of Working Alliance in Couple Therapy: A Waiting-List Controlled 1-Year Follow-Up Study

Previous research has identified working alliance as a short-term predictor of progress in couple therapy. The present waiting-list controlled 1-year follow-up study explores the long-term influence of working alliance on depression severity after intensive couple therapy. Fifteen couples-overall 30 individuals with comparatively diverse backgrounds-went through an initial waiting period and subsequent treatment phase. Each stage lasted 5 weeks. The intervention involved weekly 2-hr sessions of integrative couple therapy. Testing included the Working Alliance Inventory (WAI) and Beck Depression Inventory (BDI) before (T-0) and immediately after the waiting period (T-1) and treatment phase (T-2) alongside a 1-year follow-up (T-3). A repeated-measures analysis of covariance (n = 30) revealed a significant interaction between WAI scores and change in BDI performance (p < .001). This interaction explained almost 36% of the observed repeated-measures variance. Higher WAI scores (i.e., better client-therapist relationship) reflected greater BDI reduction immediately after treatment (T-1-T-2 [95% CI]: -3.1 [+/- 3.0]; n = 15) than lower WAI scores (T-1-T-2: 1.4 [+/- 2.0]; n = 15). Conversely, lower WAI scores were associated with larger benefit at 1-year follow-up (T-2-T-3: -6.4 [+/- 2.6]) than higher WAI scores (T-2-T-3: -0.3 [+/- 2.4]). No significant change in BDI performance occurred during the waiting period. The current results consolidate working alliance as a key factor of immediate and sustained decrease in depression severity after intensive couple therapy. However, trajectories of change over a 1-year follow-up period suggest that poorer working alliance may not diminish this decrease numerically but rather delay its onset in time.